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vrpatilisl
30th November 2011, 12:13
hi
There are default 3 ref.frame and 3 B frame. What frame should i use get output mkv with max. Quality. And how to get Dvd rip with level 4.1 and 5 automaticaly, means not selecting these 4.1 and 5 from dropdown list but keeping to automatic but with max.setting so that these value goes automaticly to 4.1 or 5. The normal value in Dvd rip i get is high @ 3.0,with max.setting. And crf 18 in handbrake/vidcoder.
Thanxs

LoRd_MuldeR
30th November 2011, 20:46
Your video stream will come out at the lowest possible `Profile@Levelī that meets all the requirements of your stream.

Some of these requirements are a direct consequence of your encoder settings (e.g. CABAC requires at least "Main" profile), some requirements depend only on the source (e.g. each Level has a "Resolution @ Framerate" limit) and some requirements depend on both of them (e.g. the Level limits the size of the Decoded Picture Buffer, which is used to hold the reference frames, but the exact number of reference frames that fit into the buffer depends on the resolution of the video).

See for details:
http://en.wikipedia.org/wiki/H.264/MPEG-4_AVC#Levels

About B-Frames: The B-Frame option of x264 only defines an upper bound! Still x264 will decide the "optimal" number of consecutive B-Frames. Thus allowing up to 16 B-Frames (the maximum in x264) always is safe, but x264 will rarely actually go that high. And 16 B-Frames will be slow. Allowing less than 16 consecutive B-Frames mainly is an encoding speed optimization. You should trust on the x264 preset system for this. I think the default value is 3, slower presets use more.

Marin85
1st December 2011, 10:15
About B-Frames: The B-Frame option of x264 only defines an upper bound! Still x264 will decide the "optimal" number of consecutive B-Frames. Thus allowing up to 16 B-Frames (the maximum in x264) always is safe, but x264 will rarely actually go that high. And 16 B-Frames will be slow. Allowing less than 16 consecutive B-Frames mainly is an encoding speed optimization. You should trust on the x264 preset system for this - I think the default value is 3.
Indeed, the keyword here is upper bound. But this should not be underestimated (pun not intended!). It appears that higher --b-frames number can help quality in a twofold way: more transperency to the source and less rapid quality drops if the encode is not bitstarved. I am yet to find the proper balance between encoding speed and quality improvements alone from using b-frames, but it seems to lie in the order of at least 9, if not more, which is noticeably more than the default number. The problem with the quality drops is really evident in static scenes, but I will post some materials to it later.

vrpatilisl
2nd December 2011, 15:04
hi
I have seen the dvdrips with 16reference frame. Is any significant advantage.
thanxs

Marin85
2nd December 2011, 15:21
hi
I have seen the dvdrips with 16reference frame. Is any significant advantage.
thanxs
Where have you seen them?

LoRd_MuldeR
2nd December 2011, 16:01
Where have you seen them?

It obviously weren't his own rips. Otherwise he had known why he used (or not used) 16 reference frames ;)

@vrpatilisl:
Take care of Rule #6 (http://forum.doom9.org/forum-rules.htmhttp://forum.doom9.org/forum-rules.htm): We cannot discuss pirated material :sly:

16reference frame. Is any significant advantage.

Using more reference frames, even up to 16, helps quite a bit. But it's of course source-dependent. Anime usually benefits more.

As a rule of thumb: x264 uses "only" 8 ref-frames in the 'slower' preset and goes up to 16 in the 'veryslow' preset.

Also keep in mind that in Level 4.1, for example, the maximum number of refs for 720p and 1080p video are 9 and 4 respectively.